How to Build a Storage Shed? | Permit Rules First

Before building a storage shed, check local permit rules—size thresholds vary sharply, and some counties require a permit for every shed.

For the full breakdown, see our best Canvas Storage Sheds guide.

Most people start a storage shed project by picking plans and lumber. The smarter first step is a phone call or website visit to your local building department, because the rules change everything—where the shed can sit, how tall it can be, and whether you need a permit at all. In the U.S., a shed is usually a detached, one-story accessory structure, and local zoning, setback, height, and utility rules govern it from the ground up.

Do You Need a Permit for a Storage Shed?

It depends entirely on where you live. Some cities exempt small sheds, others require permits for every single one, and a few tie the requirement to what’s inside the shed.

Seattle allows a shed without a permit only when it is 120 square feet or less, single-story, on a simple concrete slab, pier blocks, or soil, unattached, outside environmentally critical areas, and used only for storage. Santa Cruz, California requires a permit for detached sheds larger than 120 square feet or 10 feet high, or any shed with electrical wiring or plumbing beyond a hose bib. Osceola County, Florida goes further—it requires a building permit for all storage sheds, including prefabricated and manufactured ones, regardless of size.

Minnesota takes a different approach, requiring all sheds to be designed and constructed per the 2020 Minnesota Residential Code. The pattern is clear: square footage alone never tells the whole story.

What Rules Decide Whether Your Shed Needs a Permit

Local codes weigh five factors, and you need to verify each one for your address.

• Size and height. The 120-square-foot threshold appears in Seattle and Santa Cruz, but other cities use different numbers. Height limits often sit around 10 feet.
• Foundation and attachment. A shed on a simple slab or pier blocks may qualify for an exemption, while a permanent foundation or attachment to the house can trigger a permit.
• Utilities. Adding electrical wiring or plumbing beyond a hose bib almost always requires a permit. Seattle notes that electrical service changes need separate coordination with Seattle City Light.
• Location. Environmentally critical areas, flood zones, and sensitive land can block a shed entirely or force extra review.
• Use. A shed used for storage stays simple. Turning it into a workshop, office, or living space changes its classification and the code requirements.

The takeaway: a cookie-cutter shed from a big-box store is never automatically permit-free.

How to Build a Storage Shed Step by Step

The build order stays mostly the same nationwide, with local rules layered on top.

Step 1: Check permits and zoning first. Call your local building department or check its website for the shed rules. Ask about permits, setbacks from property lines, height limits, and whether you need a site plan, construction plans, or engineered drawings. Osceola County and Santa Cruz both require documentation before submission, so confirm what your jurisdiction wants.

Step 2: Choose a location. Keep the shed out of environmentally sensitive areas, flood-prone spots, and utility easements. Check where underground lines run before you dig.

Step 3: Prepare the foundation. A simple concrete slab, pier blocks, or a gravel base works for most small sheds. The foundation must be level and stable, and local codes may dictate the minimum thickness or type.

Step 4: Frame the floor, walls, and roof. Build the floor frame on the foundation, then raise the walls and tie them together. Add roof trusses or rafters, then sheathing.

Step 5: Install siding, roofing, and the door. Plywood or lap siding, shingles or metal roofing, and a sturdy door complete the shell. If you added electrical or plumbing, this is when an inspection usually happens before you close up the walls.

Step 6: Schedule final inspections. Most jurisdictions inspect the foundation, framing, and final construction. Pass each one before you call the project done.

Common Mistakes That Cost Time and Money

Three errors trip up most first-time builders.

Assuming an exemption applies everywhere. Seattle’s 120-square-foot rule means nothing in Osceola County, Florida, where every shed needs a permit. Always check local rules, even if your neighbor built without one.

Forgetting that utilities change everything. A shed with electrical wiring or plumbing stops being a simple structure. Santa Cruz and Osceola both treat utility-equipped sheds as a higher tier requiring permits and code compliance.

Treating prefabricated sheds as automatically exempt. “Portable” or factory-built sheds still face local rules. Osceola County requires permits for manufactured sheds and demands that they either meet the Florida Building Code or carry the Florida Department of Community Affairs seal.

The honest summary: build the shed you want, but build it by the book for your specific address. One phone call to the building department saves you from a fine, a teardown order, or a redo.